The disclosure relates to a gas insulated switchgear monitoring and diagnosis system, particularly to a cubicle type gas insulated switchgear monitoring and diagnosis system that can remotely monitor and diagnose the state by measuring and analyzing in real time deterioration of a gas section and the operation state and the integrity assessment of a breaking unit in a cubicle gas insulated switchgear.
Gas insulated substations are stations equipped with an SF6 gas breaker to open/closing the electric circuit in the stations, breakers opening/closing electric circuits such as power transmission lines and power distribution lines are disposed in the substations, and there are an oil circuit breaker, a magnetic blast circuit breaker, a vacuum circuit breaker, and an SF6 gas breaker, in accordance with the types of insulators used in the breakers.
The SF6 gas breaker, a breaker filled with an SF6 gas having excellent dielectric strength, can be sufficiently installed even in an area of 5 to 10% of an outdoor structure substation, such that the size of the substation decreases and the installation area can be considerably decreased. Further, the nontoxic and incombustible SF6 gas is used and the charging part is sealed, unlike the outdoor structure substation, such that the substation is little influenced by climate and the insulators are prevented from being contaminated and damaged by dust, steam, and sea wind, and thus the safety is high.
The SF6 gas breaker has the advantage that it has large breaking capacity and is easily handled and it is not necessary to lubricating a hydraulic breaker. Further, the breaking unit is positioned lower, such that it is easy to check the inside. Furthermore, since it has a closed structure with high-voltage equipment, such as a disconnecting switch, an arrester, and an instrument transformer, in a metal container, the operation noise is small; therefore, it is suitable for the environment even if it is installed at any one of countries and cities, and is generally used for high-voltage substations with 66 kV or more.
The SF6 gas breaker, also called a GIS (Gas Insulated Switchgear), is used as an electric power substation equipment composite apparatus that not only opens/closes a current in a normal state, but safely opens/closes an operation even in an abnormal state such as a short circuit, using the excellent physical and electrical properties of the SF6, thereby protecting the system.
A CGIS (Cubicle type Gas Insulated Switchgear), a system that removes the deficit of breaking capacity and the limit in size due to the insulating performance, which are the defects of the VCB (Vacuum Circuit Breaker) or an ACB (Air Circuit Breaker) that have been used in the related art, is an indoor breaker developed in a cubicle type by insulating SF6.
The cubicle type gas insulated switchgear, important equipment that controls a power distribution system, rapidly cuts a fault current in failure. However, when the cubicle type gas insulated switchgear fails to accurately operate due to deterioration of it and an error in the breaking unit, a large accident such as a breakdown of the entire power distribution system may be caused.
In the related art, a device that monitors and diagnoses a gas insulated switchgear was used to reduce the maintenance cost and prevent a failure in the gas insulated switchgear. However, not only the device is expensive for the cubicle type gas insulated switchgear, but it is difficult to analyze the characteristics of the breaking unit because it is designed for a gas insulated switchgear.
Therefore, a person regularly examines a cubicle type gas insulated switchgear controlling power distribution in person with naked eyes and a portable measuring instrument in the existing way, rather than using a monitoring and diagnosing system, a person evaluates the integrity assessment of the breaker by examining in person the state of a coil, the state of stroke, and the operation time due to a non-load operation. A technology of a system for examination, maintenance, monitoring, and diagnosing is intensively necessary to solve the problems.